Comparison of the Ecological Traits and Boring Densities of Aromia bungii (Faldermann, 1835) (Coleoptera: Cerambycidae) in Two Host Tree Species

SIMPLE SUMMARY: The red-necked longhorn beetle Aromia bungii is an invasive, wood-boring pest that infests Rosaceae trees. Its main host species in Japan are flowering cherry (Cerasus × yedoensis ‘Somei-yoshino’) and peach (Prunus persica) trees. We evaluated which species is more vulnerable to A. bungii by investigating the ecological traits of emerging adults and the boring density of larvae and pupae. The number of emerging adults per m(3) of P. persica trunks was 10-times greater than from C. × yedoensis, and the numbers of grown larvae and pupae in the trunk were higher in P. persica logs. The number of eggs laid over the lifetime of female adults was larger for insects that emerged from P. persica. Body size, sex ratios, and adult life spans did not differ between the two host trees. This study elucidated that peach trees are more suitable hosts than cherry trees for A. bungii larvae. Although cherry trees, primarily C. × yedoensis, which are currently grown as street or ornamental trees in Japan, have been more severely affected by A. bungii to date, the greater risk in the long term is to P. persica, an agricultural species in the main producing areas surrounding the Kanto region. ABSTRACT: We investigated the ecological traits of emerging adults and the boring density in Aromia bungii-infested flowering cherry (Cerasus × yedoensis ‘Somei-yoshino’) and peach (Prunus persica) trees to evaluate their suitability as food resources for A. bungii, and their vulnerability to infestation. The number of adults per m(3) that emerged from P. persica was 10-times larger than from C. × yedoensis, and the numbers of emergence holes, entrance holes, and pupal chambers were also larger in P. persica logs. The lifetime fecundity of adults that emerged from P. persica was also higher. Elytral length, sex ratios, and adult lifespans did not differ between the two host trees. Our results indicate that peach trees provide more suitable conditions than do flowering cherry trees for A. bungii larvae. Although flowering cherry trees, primarily C. × yedoensis, which are currently grown as street or ornamental trees in Japan, have been more severely affected by A. bungii to date, the greater risk in the long term is to P. persica, an agricultural species in the main producing areas surrounding the Kanto region.